ON THE STRENGTH OF PILLARS. 
415 
Pillars with rounded ends. 
Pillars with flat ends. 
Values of x. 
Error from using 
general mean. 
Values of x. 
Error from using 
general mean. 
834-37'" 
+ TZ 
2973*70 
/ 
+ -L 
~ 13*9 
933-13 
1 
2522 
3031-50 
4- 1^5 
826-20 
1 
+ 77 
2968-70 
4" mi 
903-28 
“ 30 8 
3586-90 
CO 
CO 
go 
GO 
1 
8*9 
808-21 
+ B7 
3573-80 
CO 
g 
1 
9-2 
1041-70 
1 
9-5 
3290-30 
L CD 
1 
31-6 
917-62 
+ — 
^ 6o-6 
3214-80 
r c5 
u 
<D 
a 
1 
112-8 
996-24 
go 
mi 
2988-30 
s 
4“ 15U 
1123-50 
04 
CO 
1 
5*8 
3099-00 
+ sh 
989-95 
949-48 
§ 
1 « 
S 
'"cS 
1 
17*3 
1 
56-7 
3115-50 
3207-70 
+ -L 
* 44 
1 
~~ 149*9 
a> 
1059-50 
3 
CD 
O 
1 
8-3 
819-46 
4" 7^2 
895-02 
+ -L 
' 23*7 
880-11 
4- — 
' 16-7 
1026-60 
1 
10*9 
927-86 
4" 189 '3 
1005-30 
1 
13*8 
784-90 
4- sV 
50. The last value of x, in pillars with rounded ends, was from a pillar so short 
as evidently to have been a little crushed by the breaking weight, a matter which 
we have seen weakens a pillar (Art. 6.). 
If the results from this experiment had been omitted, the general mean would have 
been increased from 932f to 941, and the fractional errors somewhat lessened. 
Another cause of irregularity in some of these pillars has been before alluded to 
(Art. 4 7.). 
The mean values of x, above, represent the strength of a solid pillar one inch dia- 
meter, and 7 feet 6f inches long, as obtained by calculation, on the preceding prin- 
ciples, from pillars whose length was thirty times the diameter, or upwards, in those 
with flat ends, and half that length or more, in those with rounded ends. 
It was shown (Art. 31, 32.), that when the lateral dimensions of pillars are the 
